[vsnet-grb-info 12149] Swift Trigger 529076 is from Swift J1910.2-0546 and is not a GRB

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13538
SUBJECT: Swift Trigger 529076 is from Swift J1910.2-0546 and is not a GRB
DATE:    12/07/29 18:16:45 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.a.krimm at nasa.gov>

H. A. Krimm (CRESST/GSFC/USRA) for the Swift team

Further analysis of the Swift/BAT event data from Trigger 529076 (GCN Circ 
13530, Ukwatta et al) yields a significance of 5.4-sigma.  Over the time range 
we have data (T-120 to T+180 sec), the mask-weighted light curve shows constant 
emission with no significant features on time scales typical of a gamma-ray 
burst.  Therefore we conclude that this trigger was not due to a GRB.
     The XRT and UVOT positions reported in GCN Circ 13530 are consistent within 
reported errors of the position for Swift J1910.2-0546 (ATel #4144; Rau, 
Greiner, and Schady).  Also this source has been steadily brightening in the BAT 
hard X-ray transient monitor (average of 0.021 ± 0.001 ct/s/cm^2 (~100 mCrab) in 
the 15-50 keV band for 28-July-2012). Therefore we conclude that Trigger 529076 
was caused by Swift J1910.2-0546, but that low statistics in the trigger 
interval yielded a BAT position inconsistent with this known source.


-- 
Dr. Hans A. Krimm
Universities Space Research Association
CRESST and NASA Goddard Space Flight Center
Code 661,  ASD
Greenbelt, MD  20771
USA
301-286-6955
fax 301-286-0677